Re: detecting rename->commit->modify->commit

[Teemu Likonen <tlikonen@iki.fi>]

Jeff King wrote (2008-05-01 11:20 -0400):

> Hmm, looking at the code, though, 50% is supposed to be the default
> minimum. So there might actually be a bug.

I did some testing... A file, containing 10 lines (about 200 bytes),
renamed and then modified (similarity index being a bit over 50%). Git
detected the rename just fine with "git diff -M" over the rename and
change. When I edited the file even more (similarity only 40%) "git diff
-M" didn't detect the rename but "git diff -M4" did. To me it looks like
this works nicely, better than I expected, actually.

Smaller files than that do not seem to work with "git diff -M" over the
rename and changes. They can be followed with "git log --follow -p"
which works even with the two-line "hello\nworld". And of course there
is always

  git diff commit1:path1/file1 commit2:path2/file2

I'd conclude that for logs and diffs renames are detected very nicely
and there's no problem at all to get wanted information from the repo.
I wonder how this rename detection/tracking has become such a big thing,
a debate even. But maybe merges are different.